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Summary:

There was no significant difference in the number of loggerhead sea turtles (Caretta caretta) caught in the Azores (Portugal) longline swordfish (Xiphias gladius) and blue shark (Prionace glauca) fishery between straight 16/0, offset 16/0, and offset 18/0 circle hooks. Circle hooks decreased the rate of throat hooking in loggerhead sea turtles (Caretta caretta) caught in the Azores longline swordfish and blue shark fishery. Straight 16/0 circle hooks caught the most blue sharks in the Azores longline swordfish and blue shark fishery, followed by offset 18/0 circle hooks. Offset 16/0 circle hooks caught the fewest blue sharks.

Summary:

A Japanese tuna hook 3.6mm S/S caught significantly more loggerhead sea turtles (Caretta caretta) than non-offset 16/0 and 18/0 circle hooks and caught more turtles in the throat than the circle hooks in the Azores (Portugal) longline swordfish (Xiphias gladius) and blue shark (Prionace glauca) fishery. Non-offset 18/0 circle hooks caught fewer loggerhead sea turtles (Caretta caretta) than non-offset 16/0 circle hooks in the Azores longline swordfish and blue shark fishery. There was no significant difference in the number of blue sharks caught on non-offset 16/0 and 18/0 circle hooks in the Azores longline swordfish and blue shark fishery.

Summary:

Circle hooks (non-offset 16/0 and 18/0) caught significantly more target blue sharks (Prionace glauca) than J hooks in the Azores (Portugal) longline swordfish (Xiphias gladius) fishery. There was no significant difference among the hook types tested in the number of loggerhead sea turtles (Caretta caretta) caught, although J hooks had a significantly higher rate of throat capture compared with circle hooks. 

Summary:

Blue-dyed bait does not significantly reduce loggerhead (Caretta caretta) and leatherback (Dermocheles coriacea) sea turtle captures in the western Atlantic longline fishery.

Summary: Deep water setting techniques, tested on longline gear in Hawaii, reduced bycatch of sea turtles and striped marlin. Bycatch of target species, bigeye tuna, increased 1.27 times.

Summary:

To reduce turtle interactions, regulations for the Hawaii (U.S.)-based longline swordfish (Xiphias gladius) fishery required vessels to switch from using a J-shaped hook with squid bait to a wider circle-shaped hook with fish bait. Analyses of observer data showed that, following the introduction of the regulations, significant and large reductions in sea turtle and shark capture rates occurred without compromising target species catches. There was also a highly significant reduction in the proportion of turtles that swallowed hooks and a highly significant increase in the proportion of caught turtles that were released after removal of all terminal tackle. Research suggests that turtles aggregate at foraging grounds and that instituting methods to avoid real-time turtle bycatch hotspots may further reduce turtle interactions.

Summary:

To reduce turtle interactions, regulations for the Hawaii (U.S.)-based longline swordfish (Xiphias gladius) fishery required vessels to switch from using a J-shaped hook with squid bait to a wider circle-shaped hook with fish bait. Analyses of observer data showed that, following the introduction of the regulations, significant and large reductions in sea turtle and shark capture rates occurred without compromising target species catches. There was also a highly significant reduction in the proportion of turtles that swallowed hooks and a highly significant increase in the proportion of caught turtles that were released after removal of all terminal tackle. Research suggests that turtles aggregate at foraging grounds and that instituting methods to avoid real-time turtle bycatch hotspots may further reduce turtle interactions.

Summary:

In 2003 and 2004 the scallop industry, Coonamessett Farm, and the Virginia Institute of Marine Fisheries, with funding from the U.S. National Oceanographic and Atmospheric Administration (NOAA) Fisheries Service, successfully tested a series of chains that excluded turtles from entering the dredge bag. In twelve trials, divers videoed the results of placing turtle carcasses in the path of a modified scallop dredge. Turtle carcasses went over the dredge in all but three trials. Damage was assessed as “slight or none” in all valid assessments of damage to a carcass following an encounter.

Summary:

An alternative leader design reduced loggerhead (Caretta caretta) sea turtle interactions in a Chesapeake Bay (U.S.) pound net fishery for finfish. There was no change in catch of weakfish (Cynoscion regalis), croaker (Micropogonias undulates), and harvestfish (Peprilus alepidotus).

Summary: Low profile gillnets with a panel height of six feet and no tie downs or additional floats had significantly fewer interactions with sea turtles and caught significantly less bycatch than standard gillnets. Catches of the target species (flounder) were also reduced in the low profile gillnets.